10-2 Flashcards
We have more ___ than we have ____
ORN
Neurons in the bulb
Cells that synapse with ORNs
Mitral and tufted cells
How many axons of ORN synapse with one mitral or tufted cell
25,000
Glomorulus
Junction box where synapse of olfactory cells and mitral/tufted cells occurs
Cells that connect glomoruli for comparing
Periglomorular cells
Granule cells
Cross connecting cells in the olfactory bulb that process info before sending it to the brain
What does it mean that the olfactory bulb is laminated
Has many layers
How many glomoruli per smell
One per smell (they are specific to each smell)
Why are the receptors for one particular smell distributed throughout the epithelium and not all in the same area
If that one area is destroyed, you will not be able to smell that scent
Outermost layer of the olfactory bulb
Olfactory nerve layer
Layer under the olfatory nerve layer
Periglomorular cells and astrocytes
Layer under the Periglomorular cells and astrocytes
External plexiform
What is located in the external plexiform
Axons of mitral and tufted cells
Layer under the external plexiform layer
Mitral cell layer (cell bodies here)
Layer under the mitral cell layer
Internal plexiform layer
Innermost layer of the olfactory bulb
Granule cell layer
How many glomoruli are activated by one specific odorant
One or two
Mushroom body
Olfactory bulb in drosophila
What axons project throough the olfactory tract to the brain
Mitral, tufted, and granule cells
Central projections of the olfactory bulb
Olfactory tubricle and pyriform cortex, amygdala, and entorhnial cortex
Parts of the brain involved with emotion that cause smell memories
Pyriform complex and entorhial cortex
Part of the brain associated with fear conditioning
Amygdala
Functional MRI
Looking for utilization of glucose (area that the brain is active)
When is the orbitofrontal part of the brain activated
Pleasant smell
When is the pyriform activated
Intense smell
When is the amygdala activated
Intense smell
Why is the olfactory system better in other mammals than humans
More ORNs and larger olfactory bulb (proportionally)
What happens when we are tracing a new scent
Deviating from the main line (but will reach it eventually)
What happens to smell tracking when trained
Increased speed and decreased deviation
Ozone
Product of lightening or electric arc
Humans can detect ozone at ___ molecules per billion in room air
10
Humans can detect limonene (lemon) at ___ molecules per billion in room air
15 (easy to smell)
Humans can detect alcohol at ___ molecules per billion in room air
2,000 (hard to smell in air, cannot detect in air at a party)
Humans change their perception of odor quality based on ____
Concentration
Olfactory system can detect minor changes in ___
Molecular structure
___ is activated by pleasant scents and ___ is activated by unpleasant scents
Frontal
Cingulate (emotion centers)
Zinc gluconate in nose
Was wrongly used against polio and common cold. Kills olfactory receptor neurons
Saline, epinephrine, and lidocaine in nose
No effect
VNO
Vomeronasal system
Another name for the vomeronasal organ
Jacobson organ
Function of VNO
Mediate sexual, reproductive (flehman’s response), homeostatic, and aggressive responses
Stimuli for VNO
Pheromones or kairomones
Phermones
Conospecific (same animal)
Kairomones
Other animals (eg. rodent detects owl)
Classes of odorant receptor in VOR
- V1R
- V2R
VNO pathway
Hole > VNO receptors > accessory olfactory bulb (synapses) > amygdala and hypothalamus (processing)
Female brain aciviation from estrogen
Anterior hypothalamus
Male brain aciviation from estrogen
Posterior hypothalamus
Anterior hypothalamus
Hormonal reguation and emotion
Posterior hypothalamus
Attratcion and emotion
Why do womens periods sync up
Armpits of menstruating women produce estrogen. Another girl will smell and her menstrual cycle will change to match to compete for males
